Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J179/00—Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen, with or without oxygen, or carbon only, not provided for in groups C09J161/00 - C09J177/00
  • C09J179/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
  • C09J179/08—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
  • C08G18/72—Polyisocyanates or polyisothiocyanates
  • C08G18/77—Polyisocyanates or polyisothiocyanates having heteroatoms in addition to the isocyanate or isothiocyanate nitrogen and oxygen or sulfur
  • C08G18/773—Polyisocyanates or polyisothiocyanates having heteroatoms in addition to the isocyanate or isothiocyanate nitrogen and oxygen or sulfur halogens
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/02—Polymeric products of isocyanates or isothiocyanates of isocyanates or isothiocyanates only
  • C08G18/025—Polymeric products of isocyanates or isothiocyanates of isocyanates or isothiocyanates only the polymeric products containing carbodiimide groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L79/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen or carbon only, not provided for in groups C08L61/00 - C08L77/00
  • C08L79/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
  • C08L79/08—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J179/00—Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen, with or without oxygen, or carbon only, not provided for in groups C09J161/00 - C09J177/00
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
  • C08L2666/14—Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
  • C08L2666/20—Macromolecular compounds having nitrogen in the main chain according to C08L75/00 - C08L79/00; Derivatives thereof
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/38—Improvement of the adhesion between the insulating substrate and the metal
  • H05K3/386—Improvement of the adhesion between the insulating substrate and the metal by the use of an organic polymeric bonding layer, e.g. adhesive
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
  • Y10T428/2852—Adhesive compositions
  • Y10T428/2878—Adhesive compositions including addition polymer from unsaturated monomer
  • Y10T428/2887—Adhesive compositions including addition polymer from unsaturated monomer including nitrogen containing polymer [e.g., polyacrylonitrile, polymethacrylonitrile, etc.]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
  • Y10T428/2852—Adhesive compositions
  • Y10T428/2896—Adhesive compositions including nitrogen containing condensation polymer [e.g., polyurethane, polyisocyanate, etc.]

Definitions

• the present invention relates to a novel adhesive resin composition for electronic parts and an adhesive sheet using the adhesive resin composition as the main component.
• a pasty adhesive and a heat resistant substrate coated with an adhesive have hitherto been known as adhesives for a fixing treatment of electric and electronic parts, such as semiconductor chips, substrates, or lead frames.
• the adhesives used in these cases include thermosetting resin series adhesives such as epoxy resin series adhesives, acrylic resins series adhesives, or rubber-phenol resin series adhesives.
• a hot-melt type film adhesive using a thermoplastic polyimide resin can heat-adhere to an adherend in a short time.
• heat setting after adhering is not necessary but high temperature is required for working due to the high glass transition temperature of these adhesives.
• the adhesive is excellent in the low-temperature workability but because the heat resistance of such an adhesive is low, the reliability is greatly lowered.
• thermoplastic polyimide resins have a high hygroscopic property, complicated processes such as the removal of absorbed moisture by pre-drying the resins before adhering are required, and thus the productivity thereof is low.
• JP-A-62-1714, JP-A-5-239427, and JP-A-5-320611 (the "JP-A” as used herein means an "unexamined published Japanese patent application") describe adhesive resin compositions wherein in order to improve the workability as described above, a polycarbodiimide resin is blended with an epoxy resin having a relatively low molecular weight to improve the flowability thereof.
• a polycarbodiimide resin is blended with an epoxy resin having a relatively low molecular weight to improve the flowability thereof.
• an epoxy resin having a relatively low molecular weight
• one object of the present invention is to provide an adhesive resin composition having excellent various properties.
• Another object of the present invention is to provide an adhesive sheet using the adhesive resin composition.
• an adhesive resin composition comprising a polycarbodiimide resin represented by following formula (1) and a bisalkenyl-substituted nadimide represented by following formula (2): wherein A represents a divalent organic group and n represents a positive integer, wherein R 1 and R 2 each independently represents a hydrogen atom or a methyl group and R 3 represents a diamine residue.
• an adhesive sheet comprising the above-described adhesive resin composition as the main component.
• an adhesive sheet comprising a support having formed on at least one surface thereof the above-described adhesive resin composition.
• JP-A-7-286140, JP-A-7-258353. and JP-A-7-330872 describe resin compositions wherein the bisalkenyl-substituted nadimide, which is the essential component in the present invention, is blended with, for example, a thermosetting coating material having excellent heat resistance, bismaleimide, or an epoxy resin.
• a thermosetting coating material having excellent heat resistance, bismaleimide, or an epoxy resin.
• the degree of polymerization (n) of the polycarbodiimide resin which is the one component of the adhesive resin composition of the present invention, but the degree of polymerization is preferably from 2 to 200, and more preferably from 8 to 40.
• the compounding ratio of the bisalkenyl-substituted nadimide compound, which is another component of the composition of the present invention, to the polycarbodiimide resin is determined by considering the workability and the adhesive property of the adhesive sheet of the present invention.
• the compounding amount of the bisalkenyl-substituted nadimide compound is from 1 to 100 parts by weight, preferably from 5 to 80 parts by weight, and more preferably from 10 to 60 parts by weight, per 100 parts by weight of the polycarbodiimide resin. If the compounding amount of the bisalkenyl-substituted nadimide compound is less than 1 part by weight, the addition effect of the bisalkenyl-substituted nadimide compound is not obtained. On the other hand, if the compounding amount of the bisalkenyl-substituted nadimide compound exceeds 100 parts by weight, the strength of the adhesive sheet is lowered, which is not preferred.
• the polycarbodiimide resin used in the present invention can be produced by a conventional method.
• the polycarbodiimide resin can be obtained by reacting an organic diisocyanate in an organic solvent in the presence of a carbodiimidation catalyst as disclosed in L.M.Alberino et al., Journal of Applied Polymer Science , 21 , 1999(1977), JP-A-2-292316, and JP-A-4-276359.
• the organic diisocyanate used in the above reaction for obtaining the polycarbodiimide resin includes aromatic diisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1-methoxyphenyl-2,4-diisocynate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethoxy-4,4'-diphenylmethane diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocynate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyl-4,4'-diphenyl ether diisocyanate, or o-tolylene diisocyanate; and aliphatic diisocyanates such as 4,4-methylenebis(cyclohexyl isocyanate), bis(isocyanate methyl)cyclohexane, isophorone diisocyanate
• the organic diisocyanate produced from a diamine by the following conventional method can be used. That is, there are, for example, a method of reacting the corresponding diamine with phosgene, diphenyl carbonate, and carbonyl diimidazole; and a method of producing an organic diisocyanate from a dicarboxylic acid by a Curtius rearrangement.
• the organic diisocyanate may be produced by a method of producing the diisocyanate by the thermal decomposition of the corresponding urethane, etc., as described in G. Greber, et al., Angew. Int. Ed. , Vol. 7, No. 12, 941(1968) and V.L.K. Valli, et al., Journal of Organic Chemistry , Vol. 60, 257(1995).
• Aromatic diamines are suitably used as the starting diamines for producing such diisocyanates.
• aromatic diamines examples include 2,2'-bis[4-(4-aminophenoxyphenyl)]propane, 2,2'-bis[4-(4-aminophenoxyphenyl)]-hexafluoropropane, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,4-diaminotoluene, 2,6-diaminotoluene, diaminodiphenylmethane, 4,4'-diamino-2,2'-dimethyl, and bis(trifluoro)biphenyl, although the diamines are not limited to these compounds.
• organic diisocyanates can be used alone or as copolymers of the mixtures of two or more kinds of them.
• a solvent used for the production of the above-described diisocyanates can be conventional solvents for these reactions.
• the solvent which can be used are halogenated hydrocarbon series solvents such as tetrachloroethylene, 1,2-dichloroethane, or chloroform; ketone series solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, or cyclohexanone; cyclic ether series solvents such as tetrahydrofuran, or dioxane; or the mixtures thereof.
• the carbodiimidation catalyst which can be used for producing the polycarbodiimide resin in the present invention is phosphorene oxides, and examples thereof include 3-methyl-1-phenyl-2-phosphorene-1-oxide, 1-phenyl-2-phosphorene-1-oxide, 3-methyl-2-phosphorene-1-oxide,1-ethyl-2-phosphorene-1-oxide, 1-methyl-2-phosphorene-1-oxide, and 3-phosphorene isomers thereof.
• the conventional bisalkenyl-substituted nadimides described in JP-A-59-80662, JP-A-60-178862, JP-A-61-18761, and JP-A-63-170358 can be used as the bisalkenyl-substituted nadimide which is another indispensable component for the adhesive resin composition of the present invention.
• the bisalkenyl-substituted nadimide can be generally produced by the reaction of the corresponding alkenyl-substituted nadic acid anhydride and a diamine.
• the bisalkenyl-substituted nadimides include bisallyl-substituted nadimides such as N,N'-ethylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide), N,N'-trimethylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarobxyimide), N,N'-hexamethylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide, or N,N'-dodecamthylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide), wherein the diamine is an aliphatic diamine.
• bisalkenyl-substituted nadimides include N,N'-p-phenylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide), N,N'-m-phenylene-bis(allylbicyclo[2,2,1]hepto-5-ene 2,3-dicarboxyimide), bis ⁇ 4-(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide)phenyl ⁇ methane, and bis ⁇ 4-(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide)phenyl ⁇ ether, wherein the diamine is an aromatic diamine, and also include N,N'-p-xylylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide), and N,N'-m-phenylene-bis(allylbicy
• These bisalkenyl-substituted nadimides can be used alone or as a mixture thereof.
• a curing catalyst for the polycarbodiimide resin and the bisalkenyl-substituted nadimide can be used together.
• the amount of the curing catalyst used is from 0.01 to 30 parts by weight, and preferably from 0.5 to 5 parts by weight, per 100 parts by weight of the sum of both the resins.
• the curing catalyst includes organic peroxides, onium salts, cationic catalysts, and organic group-containing metal compounds.
• the heat resistant resin of the present invention may further contain fine organic filler in the range of not reducing the workability and the heat resistance of the resin.
• the heat resistant resin may also contain, if necessary, various additives such as a smoothing agent, a leveling agent, or a defoaming agent.
• the adhesive resin composition of the present invention can be used as a varnish by dissolving the polycarbodiimide resin and the bisalkenyl-substituted nadimide compound in a common solvent and further can be used as an adhesive sheet by molding the resin composition into a film by a conventional method.
• the thickness of the adhesive sheet is generally from 1 to 2,000 ⁇ m but the thickness is not limited to this range and can be appropriately determined according to the adhering purpose. Also, the form and the size of the adhesive sheet can be appropriately determined according to the kind of an adherend such as lead frames, or semiconductor chips.
• one or more kinds of various inorganic powders composed of a metal or an alloy, such as aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, or solder; ceramics such as alumina, silica, magnesia, or silicon nitride; or carbon can be, if necessary, compounded with the resin composition.
• a metal or an alloy such as aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, or solder
• ceramics such as alumina, silica, magnesia, or silicon nitride
• carbon can be, if necessary, compounded with the resin composition.
• the coating temperature of the adhesive sheet is from 20 to 150°C, preferably from 50 to 120°C, and more preferably from 70 to 100°C. If the coating temperature is lower than 20°C, the solvent may remain in the coated film. If the coating temperature is higher than 150°C, heat setting of the coated film may proceed.
• the film of the adhesive resin composition of the present invention may be formed on a support.
• a solution of the adhesive resin composition of the present invention may be coated on a support or the lamination-type adhesive sheet may be prepared by laminating the previously formed film of the adhesive resin composition on a support by press, etc.
• a metal foil, an insulating film, etc. can be used as the support.
• the metal foil suitably used includes a foil of aluminum, copper, silver, gold, nickel, indium, chromium, lead, tin, zinc, palladium, and iron.
• the foil may be a foil of the single metal or an alloy of plural metals.
• the insulating film which can be used is various films having a heat resistance and a chemical resistance, such as films of polyimide, a polyester, or polyethylene terephthalate.
• the metal foil and the insulating film may be used alone or may be used in the form of a two-layer structure of the two elements, that is, two layer substrate of the metal foil/the insulating film may be used.
• the two layer substrate is, for example, a copper/polyimide two layer substrate.
• the adhesive sheet of the present invention is heat-cured by a heat treatment to show a strong adhesive force, and also becomes a cured product having a low hygroscopic property.
• the heat treatment can be carried out by an appropriate method such as a heater, a ultrasonic wave, and ultraviolet rays.
• the adhesive sheet of the present invention can be preferably used for the adhesive treatment of various materials, and can be particularly preferably used for the fixing treatment and the surface protection of electric and electronic parts typified by semiconductor chips, lead frames, etc., requiring a low hygroscopic property and a fixing treatment of a high reliability.
• the adhesive sheet of the present invention is excellent in the points of, for example, having a low thermal expansion coefficient, being excellent in the dimensional stability to temperature change, having a low hygroscopic property, being enriched in flexibility and being easily handled, showing a good adhesive property to semiconductor elements, and having a good storage stability.
• a varnish is prepared using the adhesive resin composition of the present invention, and a metal foil having an adhesive layer prepared by coating the varnish on one surface of the metal foil followed by drying is particularly useful for the production of multilayer circuit substrates, etc.
• the adhesive force was 1,100 g/cm. Also, the hygroscopicity of the adhesive sheet was 0.1% or lower, and when the adhesive sheet was allowed to stand at room temperature for one month, the adhesive property thereof was not lowered.
• An adhesive sheet was prepared in the same manner as in Example 1 except that 100 g of BANI-H was used.
• the adhesive force was 1,000 g/cm.
• the hygroscopicity of the adhesive sheet was 0.1% or lower, and when the adhesive sheet was allowed to stand at room temperature for one month, the adhesive property thereof was not lowered.
• An adhesive sheet was prepared in the same manner as in Example 1 except that 50 g of bis ⁇ 4-(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimido)phenyl ⁇ methane (BANI-M, trade name, manufactured by Maruzen Petrochemical Company, Ltd.) (hereinafter referred to as "BANI-M”) was used in place of BANI-H.
• BANI-M bis ⁇ 4-(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimido)phenyl ⁇ methane
• BANI-M bis ⁇ 4-(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimido)phenyl ⁇ methane
• BANI-X N,N'-p-xylylene-bis(allylbicyclo[2,2,1]hepto-5-ene-2,3-dicarboxyimide)
• BANI-X trade name, manufactured by Maruzen Petrochemical Company, Ltd.
• the resulting solution was coated on a rough surface of electrolytic copper foil having a thickness of 35 ⁇ m, dried by hot air at 90°C for 30 minutes, and further dried at 150°C for 1 hour to obtain an adhesive sheet of the present invention.
• the adhesive force was 1,100 g/cm.
• the hygroscopicity of the adhesive sheet was 0.1% or lower, and when the adhesive sheet was allowed to stand at room temperature for one month, the adhesive property thereof was not lowered.
• An adhesive sheet was prepared in the same manner as in Example 1 except that an epoxy resin (EPIKOTE 828, trade name, made by Yuka Shell Epoxy K.K.) in place of BANI-H.
• an epoxy resin EPIKOTE 828, trade name, made by Yuka Shell Epoxy K.K.
• the adhesive force was 750 g/cm.
• the hygroscopicity of the adhesive sheet was 0.5%.
• the adhesive force was similarly measured. As a result, the adhesive force was lowered to 280 g/cm, and thus the storage stability thereof was low.
• An adhesive sheet was prepared in the same manner as in Example 1 except that BANI-H was not added.
• the adhesive force was 50 g/cm.
• An adhesive sheet was prepared in the same manner as in Example 4 except that BANI-X was not added.
• the adhesive force was 30 g/cm.
• the adhesive resin composition of the present invention and the adhesive sheet using the resin composition have a low hygroscopic property, are excellent in the storage stability, and can be stored for a long period of time at room temperature,
• the adhesive resin composition and the adhesive sheet using the resin composition are excellent in the adhesive property with Ni-Fe base alloys such as a 42 alloy (42% Ni-Fe base alloy), a 45 alloy (45% Ni-Fe base alloy), or a 36 alloy (36% Ni-Fe base alloy)
• they have very high industrially utilizing value as microelectronics materials, semiconductor mounting martials, etc.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Adhesives Or Adhesive Processes (AREA)

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• 1997
  • 1997-09-19 US US08/934,398 patent/US5830949A/en not_active Expired - Fee Related
  • 1997-09-23 DE DE69726532T patent/DE69726532T2/de not_active Expired - Fee Related
  • 1997-09-23 EP EP97116579A patent/EP0832907B1/de not_active Expired - Lifetime
  • 1997-09-25 KR KR1019970048603A patent/KR100306519B1/ko not_active IP Right Cessation
  • 1997-09-26 CN CN97119211A patent/CN1091776C/zh not_active Expired - Fee Related

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